html,body,div,ul,li{
    margin: 0;
    padding:0;
}

.nav{
    float:left;
}
.nav li{
    padding:5px 10px;
    border:1px solid;
    margin-bottom:-1px;
    cursor:pointer;
}
.nav li.cur{
    background-color: #CCC;
}

.box{
    float:left;
    margin-left:-1px;
}
.box div{
    display:none;
    width:500px;
    height:300px;
    border:1px solid;
}
